Application of the method of nonstationary waveguide equations to simulating pulsed processes in irregular transmission lines

The potentialities of the model of nonstationary waveguide equations for describing pulsed processes in irregular transmission lines are studied using planar lines as an example. The problem of high-accuracy controllable-error numerical simulation is discussed. Typical examples of simulating ultra-wide-band electromagnetic pulses with an initial TEM structure in terms of time-domain representation are presented with emphasis on the interaction of the pulses with irregularities, including their transformation into longitudinal waves. Both lumped and distributed irregularities are addressed: deep corrugations that cover 90% of the transmission line’s aperture (distributed irregularities) and these corrugations in combination with sharp kinks at the boundary surfaces and permittivity steps at the boundaries of the dielectric filling (lumped irregularities). It is shown that a relative rms error involved in the calculated field intensity of no higher than 10⁻⁴ is easy to achieve.